Here's how I did it when I got the same notification a couple of days ago. Hopefully, you have Root Explorer (and if you don't, I highly recommend it because it's so worth the couple of bucks).

1. In Root Explorer, go to /system/
2. Tap Mount R/W at the top, then long-press on build.prop and scroll down to Open in Text Editor
3. Once the file is open as a text file, scroll down until you see the line that says: "ro.build.fingerprint=verizon/voles/sholes/sholes:2.2/FRG01B/45394:user/release-keys" and change it to read as follows:
ro.build.fingerprint=verizon/voles/sholes/sholes:2.2/FRG22D/50454:user/release-keys
4. Tap the back key and say "Yes" when it asks you to save (it will automatically back up the original file for you)
5. Tap Mount R/O at the top
6. Reboot

You will no longer get the OTA update notifications, because Verizon will believe you already have it.